Blue dye with particularly high purity and positive triboelectric control effect

ABSTRACT

A dye base sulfate and method of making are described. The dye base sulphate of formula (I) is produced with a residual amine content of less than 2000 ppm, as determined by HPLC, by precipitation of the dye base, made by Friedel-Crafts alkylation, substitution and hydrolysis, as the dye base sulphate is a) taken up in water and subjected to a first steam distillation then filtered and optionally dried at 50 to 180° C., b) the pressed cake is treated with water or the optionally dried dye base sulphate is moistened with water, c) subjected to a further steam distillation and filtration and d) dried at 50 to 180° C.

The present invention is situated within the field of triphenylmethanecolorants. Triphenylmethane colorants are of great industrial importancein the production of blue printing inks.

U.S. Pat. No. 3,671,553 describes a specific process for preparingparticularly pure triphenylmethane dyes. Nevertheless the products thusprepared contain up to 1% anilines (by HPLC) as residue from thesynthesis.

U.S. Pat. No. 5,061,585 describes a specifically substitutedtriaminotriphenylmethane colorant as a positive charge control agent forelectrophotographic toners and developers. This compound, however, has arelatively high level of environmentally critical impurities,particularly aniline and chlorobenzene. Aniline and chlorobenzene arereactants for the synthesis of the target substance which, as a resultof incomplete reaction or excesses, are entrained as impuritiesthroughout the production operation into the end product. For instance,the aniline content, measured by means of gas chromatography inheadspace tubes (GC-HS) after thermal exposure at 120° C. for 1 hour, isbetween about 1000 and 2500 ppm, while by means of high-performanceliquid chromatography (HPLC) on samples fully dissolved in methanolabout 9000-10 000 ppm of aniline are measured. In the case of thecompound described a distinct chlorobenzene peak is also detected.Triphenylmethane colorants having an aniline content of below 2000 ppm(by HPLC) have not been disclosed to date.

It is therefore an object of the invention to providetriaminotriphenylmethane colorants having a primary aromatic amine—inparticular, aniline and m-toluidine—content of below 2000 ppm.

A further object is to provide a colorant having a significantly reducedlevel of inorganic cations and anions, such as Na⁺, K⁺, Al³⁺, SO₄ ²⁻ orCl⁻, for example. This reduced amount of inorganic ions can be measured,for example, by means of conductivity on an aqueous suspension of theproduct.

It has been found that this object can be achieved by a new kind ofpurifying and isolating process, as described below.

The invention provides a process for preparing a compound of the formula(1)

by Friedel-Crafts alkylation of p-chlorobenzotrichloride withchlorobenzene, substitution of the aromatically bonded chlorine byaniline and m-toluidine, alkaline hydrolysis to give the dye base, andprecipitation as the dyebase sulfate of the formula (1), which comprises

-   a) taking up the dyebase sulfate in water and subjecting it to a    first steam distillation, then filtering it and drying, where    appropriate, at from 50 to 180° C.,-   b) adding water to the presscake or pasting the dyebase sulfate,    where it has been dried, with water,-   c) subjecting it to a further steam distillation and filtration-   d) and to drying at from 50 to 180° C.

The invention further provides a compound of the formula (1)characterized by a primary aromatic amine—in particular, aniline andm-toluidine—content of less than 2000 ppm, preferably less than 1000ppm, in particular less than 500 ppm, as determined by HPLC. For thispurpose the compound of the formula (1) is dried at 120° C. for about 1hour, dissolved in methanol, and analyzed by HPLC (eluent:methanol/water; column: RP-select B).

Additionally in the compound of the invention the said amine content,measured by means of GC-HS following thermal exposure at 120° C. for 1hour, is below 800 ppm, preferably below 500 ppm, more preferably below300 ppm.

Whereas the HPLC method detects the entire amine content of thesubstance (amine+amine sulfate), the GC-HS methods detects only thevolatile fraction of the compounds in the gas space over the substance.

Furthermore, the chlorobenzene content after conditioning at 120° C. for1 hour, as measured by means of GC-HS, is below 500 ppm, preferablybelow 150 ppm, more preferably below 70 ppm.

Moreover, the conductivity of a 5% aqueous dispersion of the product ofthe invention is between 0.001 and 1.5 mS/cm, preferably between 0.01and 1 mS/cm.

The process of the invention is preferably conducted as follows: Firstof all p-chlorobenzotrichloride is reacted in a Friedel-Crafts reactionwith chlorobenzene under the catalytic effect of aluminum trichloride.The aromatically bonded chlorine in the Friedel-Crafts product is thensubstituted by aniline and m-toluidine in solution in chlorobenzene. Inthe next step the resulting intermediate is hydrolyzed with aqueoussodium hydroxide solution to give the free “dye base”. Thereafter thedesired product is precipitated in the form of the “dyebase sulfate”from the chlorobenzene solution with aqueous sulfuric acid solution in aprecipitation cascade with downstream filtration. The precipitatedproduct is subsequently taken up in water, which is at a temperature of70 to 100° C., preferably at 90 to 100° C., and subjected to subsequentsteam distillation and also to a downstream aqueous filtration in orderto remove the water-soluble aniline sulfate. The product can then bedried in a drying operation, in for example a rack dryer, forced airdryer or paddle dryer, or a combination thereof, at a temperature offrom 50 to 180° C., preferably from 80 to 160° C., more preferably from90 to 150° C., where appropriate under reduced pressure of down to 10⁻⁴bar, at for example 50 to 100 mbar. Following filtration the productpresscake is admixed with water in a ratio of from 1:1 to 1:1000,preferably from 1:2 to 1:100, more preferably from 1:2 to 1:50.Alternatively, if drying has been carried out, the dried product thusobtained is pasted up in the proportions described and again issubjected to a steam distillation and filtration. Drying can then berepeated under the same conditions as described above. The additionalstep of admixing the presscake with water or the step of pasting up thedried material with water, followed by the steam distillation andfiltration, can be repeated from 1 to 10 times, preferably from two tofour times, with the drying of the presscake being carried out asdescribed above in every case after the final repetition.

In order to raise the efficiency of the removal of the impurities fromthe product it may be sensible to carry out wet grinding of the aqueousproduct suspension before the first steam distillation and/or before oneor more further steam distillations. This wet grinding operation can becarried out, for example, by means of a toothed disk mill, pinned diskmill or bead mill, giving a particle size d₅₀ of from 5 nm to 1 mm,preferably from 1 μm to 600 μm, for the ground particles in thesuspension. This step increases the access of the water to theimpurities in the enclosed particles and so makes the removal by meansof steam distillation and aqueous filtration more efficient.

The dried dyebase sulfate can subsequently be adjusted to a desiredparticle size by grinding. Examples of advantageous apparatus hereinclude air jet mills, cutting mills, hammer mills, bead mills, andimpact mills. The target particle size, determined by means ofevaluation under a light microscope or by laser light diffraction anddefined by the d₅₀ value, is appropriately between 0.01 μm and 1000 μm,preferably between 0.1 and 500 μm, and very preferably between 0.5 and400 μm. It is particularly advantageous if the grinding operationresults in a narrow particle size. Preference is given to a range Δ(d₉₅-d₅₀) of less than 500 μm, in particular less than 400 μm.

The compound of the invention contains predominantly crystallinefractions but also includes amorphous fractions.

The product of the invention can be used for pigmenting high molecularmass organic materials of natural or synthetic origin: for exampleplastics, resins, paints, paints, or electrophotographic toners anddevelopers, and also inks, including printing inks. Examples of highmolecular mass organic materials are cellulose ethers and celluloseesters, such as ethylcellulose, nitrocellulose, cellulose acetate orcellulose butyrate, natural resins or synthetic resins, such aspolymerization resins or condensation resins, for example, amino resins,especially urea-formaldehyde and melamine-formaldehyde resins, alkydresins, acrylic resins, phenolic resins, polycarbonates, polyolefins,such as polystyrene, polyvinyl chloride, polyethylene, polypropylene,polyacrylonitrile, polyacrylates, polyamides, polyurethanes orpolyesters, rubber, casein, silicone, and silicone resins, individuallyor in mixtures. Furthermore the product of the invention is alsosuitable for use as a colorant in rubber materials, office articles,wood coatings, and cleaning products, and also in artist's colors.Examples of typical printing inks are offset inks, illustration gravureinks, and printing inks for aqueous and solventborne packaging printingand for flexographic printing. The compound of the invention can be usedas a colorant for printing inks, for example, by converting it into asulfonated stage and aftertreating the product to form a powder or apaste. Examples of typical commercial names in this context are ReflexBlue R54, Reflex Blue A5H-R, Reflex Blue A5H-R31, Reflex Blue A6H-R,Reflex Blue A6H-R31 or Reflex Blue A6L-R31. Typical paints areautomotive OEM and refinish paints, industrial paints, and architecturalpaints (e.g., polymer renders or emulsion paints). Typical plasticscolorations are those, for example, in plasticized and unplasticized PVC(polyvinyl chloride), polyolefins or polystyrenes.

It matters not whether the high molecular mass organic compoundsmentioned are in the form of plastic masses, melts or spinningsolutions, paints, coating materials or printing inks. Depending on theintended utility it is found advantageous to use the product of theinvention as a blend or in the form of preparations or dispersions.Based on the high molecular mass organic material for coloring, theproduct of the invention is used in an amount of from 0.05 to 70% byweight, preferably from 0.1 to 15% by weight.

The product of the invention is also suitable as a colorant and chargecontrol agent in electrophotographic toners and developers, such asone-component or two-component powder toners (also called one-componentor two-component developers), magnetic toners, liquid toners,polymerization toners, and specialty toners. Typical toner binders areaddition-polymerization resins, polyaddition resins and polycondensationresins, such as styrene, styrene-acrylate, styrene-butadiene, acrylate,polyester, and phenol-epoxy resins, polysulfones, polyurethanes,individually or in combination and polyethylene and polypropylene whichmay contain further ingredients, such as charge control agents, waxes orflow assistants, or may be modified with these additives subsequently.

The product of the invention is additionally suitable as a colorant andcharge control agent in powders and powder coating materials, especiallyin triboelectrically or electrokinetically sprayable powder coatingmaterials which are employed for coating the surfaces of articles made,for example, of metal, wood, plastic, glass, ceramic, concrete, textilematerial, paper or rubber. As a charge control agent the product in thiscase brings about an increase in the intrinsic electrostaticcharacteristics of the powder or powder coating material. Typical powdercoating resins employed are epoxy resins, carboxyl- andhydroxyl-containing polyester resins, polyurethane, and acrylic resins,together with customary hardeners. Resin combinations are also employed.For example epoxy resins are frequently used in combination withcarboxyl- and hydroxyl-containing polyester resins. Typical hardenercomponents (depending on the resin system) are, for example, acidanhydrides, imidazoles, and dicyandiamide and derivatives thereof,blocked isocyanates, bisacylurethanes, phenolic resins and melamineresins, triglycidyl isocyanurates, oxazolines, and dicarboxylic acids.

The blue colorant used in accordance with the invention can also becombined with further positive or negative charge control agents inorder to obtain good performance chargeabilities, the overallconcentration of the charge control agents being appropriately between0.01 and 70% by weight, preferably between 0.05 and 20% by weight, morepreferably between 0.1 and 5% by weight, based on the total weight ofthe electrophotographic toner, developer, powder or powder coatingmaterial.

Examples of suitable further charge control agents include thefollowing: other triphenylmethanes; ammonium and immonium compounds,iminium compounds; fluorinated ammonium compounds and fluorinatedimmonium compounds; biscationic acid amides; polymeric ammoniumcompounds; diallylammonium compounds; aryl sulfide derivatives; phenolderivatives; phosphonium compounds and fluorinated phosphoniumcompounds; calix(n)arenes, cyclically linked oligosaccharides(cyclodextrins) and their derivatives, especially boron esterderivatives, interpolyelectrolyte complexes (IPECs); polyester salts;metal complex compounds, especially salicylate-metal complexes andsalicylate-nonmetal complexes, salts of ionic structural silicates,hydroxycarboxylic acid-metal complexes and hydroxycarboxylicacid-nonmetal complexes, benzimidazolones; azines, thiazines or oxazineswhich are listed in the Colour Index as Pigments, Solvent Dyes, BasicDyes or Acid Dyes.

Particular preference is given to the following charge control agents,which, individually or in combination with one another, can be combinedwith the blue colorant used in accordance with the invention:

-   triphenylmethanes, as described for example in U.S. Pat. No.    5,061,585;-   ammonium compounds and immonium compounds, as described for example    in U.S. Pat. No. 5,015,676;-   fluorinated ammonium compounds and fluorinated immonium compounds,    as described for example in U.S. Pat. No. 5,069,994; biscationic    acid amides, as described for example in WO 91/10172;    diallylammonium compounds, as described for example in DE-A-4 142    541, DE-A-4 029 652 or DE-A-4 103 610;-   aryl sulfide derivatives, as described for example in DE-A-4 031    705;-   phenol derivatives, as described for example in EP-A-0 258 651;    phosphonium compounds and fluorinated phosphonium compounds, as    described for example in U.S. Pat. No. 5,021,473 and U.S. Pat. No.    5,147,748;-   calix(n)arenes, as described for example in EP-A-0 385 580;-   benzimidazolones, as described for example in EP-A-0 347 695;-   cyclically linked oligosaccharides, as described for example in    DE-A-4 418 842;-   polyester salts, as described for example in DE-A-4 332 170;-   cyclooligosaccharide compounds, as described for example in DE-A-1    97 11 260;-   interpolyelectrolyte complexes, as described for example in DE-A-197    32 995, salts of ionic structural silicates, as described for    example in PCT/EP 00/11217.

Additionally suitable, particularly for liquid toners, aresurface-active, ionic compounds and what are called metal soaps.

Particularly suitable are alkylated arylsulfonates, such as bariumpetronates, calcium petronates, barium dinonyinaphthalenesulfonates(basic and neutral), calcium dinonylsulfonate or sodiumdodecylbenzenesulfonate, and polyisobutylenesuccinimides (Chevron's Oloa1200).

Also suitable are soya lecithin and N-vinylpyrrolidone polymers.

Also suitable are sodium salts of phosphated monoglycerides anddiglycerides with saturated and unsaturated substituents, AB diblockcopolymers of A: polymers of 2-N,N-dimethylaminoethyl methacrylatequaternized with methyl p-toluenesulfonate, and B: poly-2-ethylhexylmethacrylate.

Also suitable, especially in liquid toners, are divalent and trivalentcarboxylates, especially aluminum tristearate, barium stearate, chromiumstearate, magnesium octoate, calcium stearate, iron-naphthalite, andzinc naphthalite.

Also suitable are chelating charge control agents (EP 0 636 945 A1),metallic (ionic) compounds (EP 0 778 501 A1), phosphate metal salts, asdescribed in JA 9 (1997)-106107. Also suitable are azines of thefollowing Colour Index Numbers: C.I. Solvent Black 5, 5:1, 5:2, 7, 31,and 50; C.I. Pigment Black 1, C.I. Basic Red 2, and C.I. Basic Black 1and 2.

The blue colorant used in accordance with the invention, alone or incombination with other such colorants or with further charge controlagents specified above, is incorporated in a concentration of from 0.01to 50% by weight, preferably from 0.05 to 20% by weight, more preferablyfrom 0.1 to 5.0% by weight, based on the total mixture, into the binderof the respective toner, developer, paint, powder coating material,electret material, or polymer requiring electrostatic separation, thisincorporation taking place homogeneously, achieved for example byextrusion or kneaded incorporation, by bead milling or with anUltraturrax (high-speed stirrer).

The compounds used in accordance with the invention can be added in theform of dried and ground powders, dispersions or solutions, presscakes,masterbatches, preparations, prepared pastes, as compounds applied fromaqueous or nonaqueous solution to suitable carriers, such as silica gel,or mixed with such carriers, TiO₂, Al₂O₃, carbon black, for example, orcan be added in some other form. It is likewise also possible for thecompounds used in accordance with the invention to be added in principleduring the actual preparation of the respective toner polymer matrix,i.e., in the course of its addition polymerization, polyaddition orpolycondensation, and also during the preparation of polymerizationtoners—for example, during the suspension polymerization or emulsionpolymerization or during the aggregation of the polymer systems to formtoner particles.

The blue colorant of the invention and also the charge control agentscan also be used in the form of fine aqueous, aqueous-organic or organicdispersions. The particle sizes (d₅₀ values) are between 1 nm and 1 μm,preferably between 50 and 500 nm. Appropriate concentrations of chargecontrol agent are between 0.01 and 50% by weight, preferably between 0.1and 30% by weight, based on the total weight of the dispersion. Theviscosity of such a dispersion is appropriately between 0.5 and 10⁶ mPas, preferably between 1 and 5000 mPa s.

In the case of aqueous or aqueous-organic dispersions the water used ispreferably in the form of distilled or demineralized water. In the caseof organic or aqueous-organic dispersions the organic medium usedcomprises one or more organic solvents, preferably from the group of themonohydric or polyhydric alcohols, their ethers and esters, e.g.,alkanols, especially those having 1 to 4 carbon atoms, such as methanol,ethanol, propanol, isopropanol, butanol or isobutanol; dihydric ortrihydric alcohols, especially those having 2 to 6 carbon atoms, e.g.,ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol,1,5-pentanediol, 1,6-hexanediol, 1,2,6-hexanetriol, glycerol, diethyleneglycol, dipropylene glycol, triethylene glycol, polyethylene glycol,tripropylene glycol, polypropylene glycol; lower alkyl ethers ofpolyhydric alcohols, such as ethylene glycol monomethyl or ethyl orbutyl ether, triethylene glycol monomethyl or ethyl ether; ketones andketone alcohols, such as acetone, methyl ethyl ketone, diethyl ketone,methyl isobutyl ketone, methyl pentyl ketone, cyclopentanone,cyclohexanone, and diacetone alcohol, for example; and amides, such asdimethylformamide, dimethylacetamide, and N-methylpyrrolidone, forexample.

For the preparation of stable dispersions it is also possible, moreover,to use customary ionic or nonionic dispersing assistants, such assulfonates, phosphates, polyphosphates, carbonates, silicates,hydroxides, metal soaps, polymers, such as acrylates, fatty acidderivatives, and glycoside compounds.

The dispersions may also include metal complexing agents, such as EDTAor NTA, for example.

The dispersions may, furthermore, comprise other customary additives,such as preservatives, biocides, antioxidants, cationic, anionic,amphoteric or nonionogenic surface-active substances (surfactants andwetting agents), devolatilizers/defoamers, and also viscosityregulators, e.g., polyvinyl alcohol, cellulose derivatives orwater-soluble natural or synthetic resins and polymers as film formersor binders to increase the adhesiveness and abrasion resistance. pHregulators employed include organic and inorganic bases and acids.Preferred organic bases are amines, such as ethanolamine,diethanolamine, triethanolamine, N,N-dimethylethanolamine,diisopropylamine, aminomethylpropanol or dimethylaminomethylpropanol,for example. Preferred inorganic bases are sodium, potassium, andlithium hydroxide, and ammonia. Further possible constituents includehydrotropic compounds, such as formamide, urea, tetramethylurea,ε-caprolactam, ethylene glycol, diethylene glycol, triethylene glycol,polyethylene glycol, butylglycol, methyl cellosolve, glycerol, sugars,N-methylpyrrolidone, 1,3-diethyl-2-imidazolidinone, thiodiglycol, sodiumbenzenesulfonate, sodium xylenesulfonate, sodium toluenesulfonate,sodium cumenesulfonate, sodium benzoate, sodium salicylate or sodiumbutylmonoglycol sulfate.

The concentration of these dispersing assistants and/or customaryadditives in the dispersion is appropriately between 0.001 and 80% byweight, preferably between 0.01 and 50% by weight, based on the totalweight of the dispersion.

In order to prepare electrophotographic color toners it is possible toadd further colorants such as organic chromatic pigments, inorganicpigments or dyes, usually in the form of powders, dispersions,presscakes, solutions or masterbatches.

The organic chromatic pigments can be from the group of the azo pigmentsor polycyclic pigments or can be mixed crystals (solid solutions) ofsuch pigments.

Preferred blue pigments and/or green pigments are copperphthalocyanines, such as C.I. Pigment Blue 15, 15:1, 15:2, 15:3, 15:4,15:6, P. Blue 16 (metal-free phthalocyanine), or phthalocyanine withaluminum, nickel, iron or vanadium as the central atom, and alsotriarylcarbonium pigments such as Pigment Blue 1, 2, 9, 10, 14, 16, 56,60, 61, 62, 68, 80; Pigment Green 1, 4, 7, 17, 36, 50 45; Orangepigments, such as P.O. 5, 13, 34, 36, 38, 43, 62, 68, 70, 72, 71, 74;Yellow pigments, such as P.Y. 12, 13, 14, 17, 74, 83, 93, 97, 111, 120,122, 139, 151, 154, 155, 174, 175, 176, 180, 174, 185, 194, 213, 214;red pigments, such as P.R. 2, 3, 4, 5, 9, 38, 48, 53, 57, 112, 122, 144,146, 147, 149, 168, 170, 175, 176, 177, 179, 181, 184, 185, 186, 188,189, 202, 207, 208, 209, 210, 214, 219, 238, 253, 254, 255, 256, 257,266, 269, 270, 272, 279; violet pigments, such as P.V. 1, 19, 23, 32,carbon black such as P. Black 7, 11, 33 or in their surface-modifiedform as described in U.S. Pat. No. 5,554,739, iron/manganese oxides; andalso mixed crystals such as those, for example, of pigments describedabove such as C.I. Pigment Violet 19 and C.I. Pigment Red 122, and alsoazo-surface-modified pigments as described in WO 01/30919.

The mixtures can be prepared in the form of powders, granules, by mixingpresscakes, spray-dried presscakes or masterbatches and also bydispersing (extrusion, kneading, roll-mill processes, bead mills,Ultraturrax, ultrasound) in the presence of a carrier material in solidor liquid form (aqueous and nonaqueous inks) and also by flushing in thepresence of a carrier material. Where the colorant is used with highproportions of water or solvent (>5%), mixing can also take place atelevated temperatures, by subsequent cooling of the mixture mass withvacuum assistance. The flushing operation can take place in the presenceor absence of organic solvents and of waxes.

Particularly appropriate for increasing the brightness but also forshading the hue are mixtures with organic dyes. Preferred such dyesinclude the following:

water-soluble dyes, such as Direct, Reactive, and Acid Dyes, and alsosolvent-soluble dyes, such as Solvent Dyes, Disperse Dyes, and Vat Dyesfor example. Examples include the following: C.I. Reactive Yellow 37,Acid Yellow 23, Reactive Red 23, 180, Acid Red 52, Reactive Blue 19, 21,Acid Blue 9, Direct Blue 199, Solvent Yellow 14, 16, 25, 56, 62, 64, 79,81, 82, 83, 83:1, 93, 98, 133, 162, 174, Solvent Red 8, 19, 24, 49, 89,90, 91, 92, 109, 118, 119, 122, 124, 127, 135, 160, 195, 212, 215,Solvent Blue 44, 45, Solvent Orange 41, 60, 63, Disperse Yellow 64, VatRed 41, Solvent Black 45, 27.

It is also possible to use dyes and pigments having fluorescentproperties, such as ®Luminols (Riedel-de Haen), in order for example toproduct anticounterfeit toners. Furthermore, the colorants may also beused in a special wax-coated form, as described in EP-A-1 204 005, incombination with the charge control agents of the invention.

Inorganic pigments, such as TiO₂ or BaSO₄, for example, are used inmixtures for lightening. Also suitable are mixtures with effectpigments, such as pearlescent pigments, Fe₂O₃ pigments (®Paliochroms),and pigments based on cholesteric polymers, which exhibit differentcolors depending on the angle of observation.

Electrophotographic toners and powder coating materials as well mayfurther comprise waxes. The term “wax” refers to a range of substances,natural or synthetically obtained, which generally have the followingproperties: they are kneadable at 20° C., ranging from firm to hard andfragile, from coarse to finely crystalline, and from transluscent toopaque, but not glasslike; they melt without decomposition at 40° C.,are of relatively low viscosity, without stringing, at just a littleabove the melting point, have a highly temperature-dependent consistencyand solubility, and can be polished under gentle pressure.

The following waxes are preferred: natural waxes such as plant waxes,e.g., carnauba wax, candellila wax, and animal waxes, e.g., beeswax,modified natural waxes, such as paraffin wax, microwaxes, semisyntheticwaxes, such as montan ester waxes, or synthetic waxes, such aspolyolefin waxes, e.g., polyethylene and polypropylene waxes,polyethylene glycol waxes, cycloolefin copolymer waxes, amide waxes,such as N,N′-distearylethylenediamine, zirconocene waxes, andchlorinated or fluorinated polyolefin waxes orpolyethylene-polytetrafluorethylene wax mixtures.

Also of interest is an electrophotographic toner, powder or powdercoating material containing from 30 to 99.99% by weight, preferably from40 to 99.5% by weight, of a customary binder, for example, a styrene,styrene-acrylate, styrene-butadiene, acrylate, urethane, acrylic,polyester or epoxy resin or a combination of the last two, from 0.01 to50% by weight, preferably from 0.05 to 20% by weight, more preferablyfrom 0.1 to 5% by weight, of the product of the invention, and, ifdesired, from 0.001 to 50% by weight, preferably from 0.05 to 20% byweight, of a further colorant and/or charge control agent, based in eachcase on the total weight of the electrophotographic toner, powder orpowder coating material.

The compound described in accordance with the invention can further beapplied to free-flow agents as an additional charge control element insuspended form or in a dry blend. The compound described in accordancewith the invention can also be used for a carrier coating.

The product of the invention is also suitable as a colorant in aqueousand nonaqueous inkjet inks and also in those inks which operate inaccordance with the hot melt process. In this context it can also beused in combination with other inks in order to produce, for example,magenta, cyan, yellow or black inks.

Inkjet inks generally contain a total of from 0.5 to 15% by weight,preferably from 1.5 to 8% by weight, of the product of the invention(reckoned on a dry basis).

Microemulsion inks are based on organic solvents and water together ifdesired with a hydrotropic substance (interface mediator). Microemulsioninks generally contain from 0.5 to 15% by weight, preferably from 1.5 to8% by weight, of the product of the invention, from 5 to 99% by weightof water and from 0.5 to 94.5% by weight of organic solvent and/orhydrotropic compound.

“Solvent based” inkjet inks contain preferably from 0.5 to 15% by weightof the product of the invention and from 85 to 99.5% by weight oforganic solvent and/or hydrotropic compounds.

Hot-melt inks are based usually on waxes, fatty acids, fatty alcohols orsulfonamides which are solid at room temperature and liquefy on heating,the preferred melting range being between about 60° C. and about 140° C.Hot-melt inkjet inks consist for example essentially of from 20 to 90%by weight of wax and from 1 to 10% by weight of the product of theinvention. Also present may be from 0 to 20% by weight of an additionalpolymer (as “dye dissolver”), from 0 to 5% by weight of dispersingassistant, from 0 to 20% by weight of viscosity modifier, from 0 to 20%by weight of plasticizer, from 0 to 10% by weight of tackifier, from 0to 10% by weight transparency stabilizer (preventing crystallization ofthe waxes for example), and from 0 to 2% by weight of antioxidant.Typical additives and auxiliaries are described for example in U.S. Pat.No. 5,560,760.

The compound of the invention is also suitable, furthermore, as an agentfor shading black, red, yellow or brown hues, for example, in toners,developers, printing inks, varnishes, plastics, rubber materials,paints, office articles, artist's colors or inkjet inks.

The product of the invention is also suitable, furthermore, as acolorant for color filters and also for both additive and subtractivecolor production, and additionally as a colorant and charge controlagent for electronic inks or electronic paper (“e-paper”), which areknown from the literature, such as, for example, from Shuichi Maeda,Kohei Gocho and Makoto Omodani, “Electrical Twisting Sticks in aTransparent Tube”, Proceedings of the International Congress of ImagingScience 2002, Tokyo, pp. 507-508.

The compound described in accordance with the invention is alsosuitable, furthermore, for the surface modification of pigment particlesas described for example in WO 01/30919 A1, U.S. Pat. No. 5,922,118 orU.S. Pat. No. 5,554,739.

The compound described in accordance with the invention, moreover, as acharge control agent may considerably enhance the charging behavior andcharge stability properties of electret materials, especially electretfibers. Typical electret materials are based on polyolefins, halogenatedpolyolefins, polyacrylates, polyacrylonitriles, polystyrenes orfluoropolymers, such as polyethylene, polypropylene,polytetrafluoroethylene, and perfluorinated ethylene and propylene, oron polyesters, polycarbonates, polyamides, polyimides, polyetherketones, on polyarylene sulfides, especially polyphenylene sulfides, onpolyacetals, cellulose esters, polyalkylene terephthalates, and mixturesthereof. Electret materials, especially electret fibers, can be used forexample to filter (ultrafine) dust. The electret materials may acquiretheir charge through corona or tribo charging.

The compound described in accordance with the invention can also be usedas a charge control agent in electrostatic separating operations,especially in operations to separate polymers. Absent charge controlagents, the triboelectrical charging behavior of low densitypolyethylene (LDPE) and high density polyethylene (HDPE) is extremelysimilar. Following the addition of charge control agent, LDPE acquires astrongly positive charge and HDPE a strongly negative charge, andaccordingly the two materials can be effectively separated. As well asapplying the charge control agents to the exterior of the polymer it isalso possible to incorporate them into the polymer, in order, forexample, to shift the position of the polymer within the triboelectricvoltage series and to obtain a corresponding separation effect. Otherpolymers can likewise be separated from one another in this way, such aspolypropylene (PP) and/or polyethylene terephthalate (PET) and/orpolyvinyl chloride (PVC), for example.

The compound described in accordance with the invention can also beused, furthermore, to separate salt minerals, by improving thesubstrate-specific electrostatic charging through its addition (surfaceconditioning).

Moreover, on account of its charge control properties, the compounddescribed in accordance with the invention can also be used as an“electroconductivity providing agent” (ECPA) in inks for inkjetprinters.

The analytical methods referred to are carried out as follows:

-   1) HPLC:    -   Column: RP-select B;    -   Eluent: methanol/water beginning with 30% methanol/70% water        then graduating over the course of 20 minutes to 50% methanol,        then to 100% methanol over the course of 10 minutes, then        remaining constant at 100% methanol for 10 minutes;    -   Temperature: 40° C.;    -   Flow rate: 0.2 ml/minute;-   2) Headspace+GC/MS:    -   a) Headspace: 120° C., 60 minutes    -   b) GC/MS        -   column: HP-624 (VOC), (0.25 mm, 60 m);        -   carrier gas: helium;        -   oven: 40° C. (2 minutes), 250° C. (20 K/minute), 250° C. (30            minutes);        -   Split ratio: 30:1

In the examples below, parts and percentages are by weight.

PREPARATION EXAMPLE

2.6 l of chlorobenzene and 600 g of aluminum chloride were combined in aflask with stirring at 25° C., after which 986 g of p-chlorobenzenetrichloride were added in portions at max. 35° C. and the mixture washeated to 60° C., stirred for 6 hours and then cooled to roomtemperature. Thereafter, at from 30 to 40° C., 520 ml of m-toluidinewere added to the mixture, which was slowly heated to 130° C. and thenstirred at this temperature for 2 hours. Then 2.1 l of aniline wereadded over the course of 3 hours and the reaction temperature was raisedto 160-165° C. The chlorobenzene was distilled off in this operation. Inorder to remove the residual chlorobenzene a gentle to moderate vacuumwas applied at from 160 to 165° C. Finally the mixture was cooled againand the vacuum was removed.

Then a second flask was charged with 3.3 l of 33% strength sodiumhydroxide solution, the reaction mixture from the first flask was addedwith stirring at about 95° C., and this mixture was stirred at 95° C.for 3 hours. Following the addition of 2 l of water to the reactionmixture and stirring, the lower, aluminate phase was separated off.Thereafter 9.2 l of chlorobenzene and 4 l of water were added to themixture, which was heated at 50° C. with stirring and again left tosettle for 1 hour. The lower, chlorobenzene phase, which contained the“blue base” was separated off and precipitated from 40% strengthsulfuric acid solution in a precipitation cascade at from about 50 to70° C., after which the “dyebase sulfate” obtained was filtered off. Theprecipitated and filtered dyebase sulfate was washed with water at 90 to100° C. and subjected to a steam distillation at 100° C., to subsequentfiltration and drying at approximately 110° C. on a rack dryer, topasting of the dried product with ten times the amount by weight ofwater, and to a second steam distillation with subsequent filtration anddrying at 110° C.

Characterization: appearance: dark blue powder aniline content: 180 ppm(GC-HS after 1 h/120° C.) aniline content: 290 ppm (HPLC inmethanol/water, after 1 h/120° C.) m-toluidine content: <50 ppm (HPLC inmethanol/water, after 1 h/120° C.) chlorobenzene content: 30 ppm (GC-HSafter 1 h/120° C.) tan δ (1 kHz): 0.03 specific resistance: 5 × 10¹³ Ωcmcrystallinity: Peaks in the X-ray diffraction diagram at the followingangles 2θ(CuKα radiation): 6.93° (moderate); 12.03° (moderate); 13.90°(moderate); 18.44° (strong); 21.13° (weak); 21.64° (weak); 22.45°(weak); 24.57° (weak); 28.14° (weak); 30.53° (weak); 32.42° (weak); theblue colorant of the invention, unlike the triphenylmethane dye known todate with a markedly higher impurity content, including for exampleaniline or chlorobenzene, does not give a (weak) peak at 2θ=6°;

-   -   IR spectrum: characteristic bands at the following wavenumbers        ν[1/cm]: 3600-3300 (several bands, weak); 3300-2600 (several        bands, weak); 2600-1700 (several bands, weak); 1650-1600 (one        band, moderate); 1600-1550 (one band, strong); 1550-1450        (several bands, moderate); 1400-1300 (two bands, strong);        1300-1200 (several bands, moderate); 1200-1150 (one band,        strong); 1150-1000 (several bands, moderate); 1000-400 (several        bands, weak);    -   DSC: no decomposition up to 250° C. (under air atmosphere);        decomposition peaks at 262° C. (weak), 295° C. (moderate),        315° C. and above (strong);    -   pH: 2.8    -   conductivity: 450 μS/cm    -   residual moisture: 1.6% (Karl-Fischer)    -   particle size distribution: d₅₀=7.4 μm, d₉₅=17.2 μm (Coulter        counter);

Use Example 1

1 part of the compound from the preparation example is incorporatedhomogeneously using a compounder over the course of 30 minutes into 99parts of a toner binder (60:40 styrene-acrylate copolymer ®AlmacrylB-1501). The resulting composition is then ground on a universallaboratory mill and subsequently classified on a centrifugal classifier.The desired particle fraction (4 to 25 μm) is activated with a carrierconsisting of magnetite particles measuring from 50 to 200 μm which havebeen coated with 90:10 styrene-methacrylate copolymer.

Measurement is carried out on a customary q/m test setup. A screen witha mesh size of 45 μm is used to ensure that when the toner is blown outno carrier is entrained with it. The measurements are made at a relativeatmospheric humidity of approximately 50%. As a function of theactivation time the q/m figures [μC/g] indicated in the table below arerecorded:

Activation time Charge q/m [μC/g] 5 min. +14 10 min. +15 30 min. +15 2 h+16

Use Example 2

The procedure of Use Example 1 is repeated but with the furtherincorporation of 5 parts of an organic pigment (carbon black ®Mogul L,Cabot).

q/m [μC/g] Ex. 5 min. 10 min. 30 min. 120 min. 2 +10 +12 +13 +14

1. A composition comprising a compound of formula (1)

and an aniline, wherein the aniline is present in an amount less than2000 ppm as determined by high performance liquid chromatography.
 2. Thecomposition as claimed in claim 1, wherein the aniline is present in anamount less than 1000 ppm.
 3. The composition as claimed in claim 1,having a conductivity of between 0.001 and 1.5 mS/cm in 5% by weightaqueous dispersion.
 4. The composition as claimed in claim 1, furthercomprising m-toluidine, wherein the toluidine is present in an amountless than 1000 ppm.
 5. The composition as claimed in claim 1, having aconductivity of between 0.01 and 1 mS/cm in 5% by weight aqueousdispersion.
 6. A colorant for pigmenting high molecular mass organicmaterials, office articles, and cleaning products comprising acomposition as claimed in claim
 1. 7. A pigmented composition comprisinga composition as claimed in claim 1, wherein the pigmented compositionis selected from the group consisting of plastics, resins, varnishes,emulsion paints, wood paints, printing inks, artists colors, rubbermaterials, inks, inkjet inks, powder coating materials, andelectrophotographic toners and developers.
 8. A colorant and chargecontrol agent for an electrophotographic or electrophotographicdeveloper comprising a composition as claimed in claim
 1. 9. An agentfor shading black, red, yellow or brown hues in a second compositioncomprising composition as claimed in claim 1, wherein the secondcomposition is selected from the group consisting of toners, developers,printing inks, varnishes, plastics, rubber materials, paints, officearticles, artists' colors and inkjet inks.